Just retired from large metro PD in CA after 30 years as a cop. Some of the above info is good, some bad. Gun laws vary from state to state, with NY, NJ, and several other anti-gun N/E states being very restrictive. ConcealedCarry.org, and several other CCW web sites have state by state laws. Some states allow "open carry", meaning loaded on the dash is ok, some even under the seat is ok, but not on your person. It is fairly easy to obtain either a Utah or Florida CCW, which allows loaded CC on your person/veh in about 30 states that have reciprocity, CA of course doesn't recognize any one else's CCW. Most states (key word "most") have no law restricting a loaded weapon (rifle/shotgun/handgun) in the living area of your RV....however, there are many restrictions on the area that is immediately under the driver's, and/or passenger's control, i.e. the cab. National and State parks are the exception. In California, if you don't possess a valid CA CCW (state permit but issued by the counry Sheriff or City Chief of Police), any concealable firearm (handgun) must be kept in a LOCKABLE container OTHER than the glovebox, with the ammo separately. A loaded magazine, if it's with the weapon in the same box, can be considered as the weapon being loaded if the officer wants to push the issue....again this DOES NOT apply to the living area of your RV, or temporary camp site, both of which are considered your residence at that time. Most officers in most states, are not going to hassle mom & pop RV'ers no matter where the weapon is in the vehicle, as long as you're not doing something stupid like brandishing it to scare the guy in the next lane who just cut you off. Remember I said "MOST". No one should ever even know you have it, unless you need it.....and if you end up needing it....a misdemenor charge of carrying it will be the LEAST of your problems. I'm a very pro-gun guy, but I''ll offer one last piece of advice.....don't carry a gun, unless.........
#1: You spend the time to become proficient with it. It's a perishable skill, so practice, practice, practice shooting and reloading.
#2: You''ve already made the decision that you WILL use it if necessary. Many people are able.....but most are not willing. Moral, legal, and liability issues should all be a part of your decision making proccess to carry a gun, so that if, God forbid, that time ever comes, you won't hesitate for those few second which can cost you or your spouse your life.
#3: Once that hammer drops, there's no calling the bullet back....no "time out" Be sure of your target and the background. Hope this helps and happy RVing.